10,11-Dihydro-5-oxo-5H-dibenzo[a,d]cycloheptene-3-acetic acid, the 3-.alpha.-substituted acetic acids and esters and salts thereof having anti-inflammatory activity are disclosed in U.S. Pat. No. 3,780,061. 10,11-Dihydro-5-oxo-5H-dibenzo[a,d]cycloheptene-2-acetic acid, the 2-.alpha.-substituted acetic acids and esters and salts thereof having anti-inflammatory activity are shown by West German OLS No. 2,409,919. Other related art can be found in U.S. Pat. No. 4,020,094.